The Sant Pau Memory Unit publishes a new study in collaboration with the University of California San Francisco. The study examines the role of neurofilament light chain (NfL) and total tau levels in plasma for the diagnosis of frontotemporal dementia and Alzheimer’s disease.
The work entitled “Plasma tau and neurofilament light in frontotemporal lobar degeneration and Alzheimer’s disease” has recently been published in the journal Neurology.
Neurofilament and tau
The clinical diagnosis of frontotemporal dementia and Alzheimer’s disease based on presented symptoms can be difficult. For this reason, tools are being developed to improve the diagnosis of these diseases and predict clinical progression or the speed of functional deterioration in each case.
Cerebrospinal fluid levels of neurofilament light (NfL) and total tau protein have been found to be especially increased in frontotemporal dementia and Alzheimer’s disease, respectively. Both measures reflect different aspects of the brain damage that occurs in these neurodegenerative diseases. The role of these measurements in blood and their combined study could be relevant.
What have we done in this study?
In this study, neurofilament light chain and total tau protein levels were compared in plasma samples from patients with frontotemporal dementia and Alzheimer’s disease. In addition, the ability of these measures to predict the degree of atrophy in brain magnetic resonance imaging, the clinical deterioration of the patients, the existence of Alzheimer’s disease in autopsy patients, and survival were analyzed.
The analyzed samples were obtained at the Memory and Aging Center of the University of California San Francisco between 2011 and 2015.
The main finding of this work was that neurofilament light chain blood levels were better than total tau levels to support the diagnosis of frontotemporal dementia, detect the level of brain atrophy, predict clinical deterioration and survival. Furthermore, the combination of neurofilament light chain blood levels with total tau protein levels did not provide additional information for diagnosis.
Relevance of the study
This study confirms that levels of neurofilament measured in plasma have higher diagnostic performance than levels of total tau protein for the diagnosis of frontotemporal dementias. Our results add to previous work supporting the use of neurofilament light chain blood levels to improve the diagnosis of patients with frontotemporal dementias.
This study has been led by Dr. Illán-Gala during his stay at the University of California San Francisco as an Atlantic Fellow for Equity in Brain Health.